Introduction: Experimental observations have shown the effect of curcumin on improving fasting blood glucose and weight loss. Curcumin is a natural yellow plant (stem), which exhibits various bio­logical activities such as anti-oxidant, anti-carcinogenic, and anti-diabetic effects. The aim of this study was to investigate the effect of curcumin supplementation on glycemic control and anthropometric indices in overweight patients with type 2 diabetes. Materials and Methods: In this randomized, double-blind, placebo-controlled trial, 53 participants with type 2 diabetes were divided randomly into the experimental and control groups to receive either 500mg curcumin or placebo capsule three times in a day for 10 weeks. Anthropometric measures including weight, height, waist circumference, hip circumference and BMI, serum levels of fasting blood sugar (FBS), Hemoglobin A1c (HbA1c), insulin, HOMA-IR and HOMA-β were determined at baseline and again 10 weeks later. Result: There were no significant differences between the two groups with regard to mean age, duration of diabetes, treatment method, drugs and sex distribution. At the end of the study the mean serum concentration of blood sugar decreased significantly between the two groups (p=0.01). Mean serum concentrations of insulin, HbA1C, HOMA-IR and HOMA-β showed no significant changes between two groups at the end of the study. Mean body weight decreased significantly in the curcumin group, compared to the controls at the end of the study (p=0.04). Mean hip circumference decreased significantly in curcumin group at the end of the study compared to the baseline (p=0.05), a difference that was significant in curcumin group, compared to the placebo group (p=0.01). At the end of the study the mean waist circumference had no significant difference between the two groups. Conclusion: This study indicated that daily administration of 1500 mg curcumin has positive effects in reducing fasting blood glucose and weight in patients with type 2 diabetes.